The influence of the density-dependent symmetry energy on the balance energy (E bal ) of directed flow from heavy ion collisions (HICs) at incident energies covered by INDRA and MSU experiments is studied, using the updated version of the ultrarelativistic quantum molecular dynamics (UrQMD) model, especially adapted to low-energy heavy ion collisions (HICs). Four mass-symmetric reactions with total mass numbers between 192 and 394 are chosen for investigating the influence of the symmetry energy on the system-mass dependence of E bal . The results show that the uncertainty in the density dependence of the symmetry potential causes changes of E bal of the order of several MeV, depending on the type of particle considered. The E bal of neutrons from HICs is particularly sensitive to the density dependence of the symmetry potential energy, while the system-mass dependence of E bal of Z = 1 particles is not. symmetry energy, directed flow, balance energy PACS number(s): 21.65.Ef, 25.70.-z, 25.75.Ld Citation:A key objective in the study of heavy ion collisions (HICs), whether using stable or unstable beams, is to collect information about the nuclear equation of state (EoS). For stable nuclei with large mass numbers, the iso-vector part of the EoS is of importance due to the fact of their neutron number N being considerably larger than their proton number Z. Even for initially isospin-symmetric systems, the isospin effect should be taken into account since isospin diffusion and distillation may occur during the non-equilibrium stages of HICs. Essentially the whole collision is an isospin non-equilibrium process [1,2]. It is also well known and quite obvious that the isospin asymmetric EoS, besides in nuclear physics, is very important for understanding many phenomena in astrophysics as, e.g., the physics of neutron stars. At present, the *Corresponding author (email: liqf@hutc.zj.cn) largest uncertainty in the EoS is believed to come mainly from the density-dependent iso-vector part, the symmetry energy. For the isoscalar part, a soft EoS with incompressibility K around 230 MeV has been extracted through comparisons with data [3,4]. Significant progress in constraining the symmetry energy has been made during the past few years. For recent reviews we refer the reader to refs. [5,6]. Despite these achievements, the density dependence of the symmetry energy, especially at supranormal densities, is still not well determined due to strong model dependences [7][8][9][10].To reduce the model influence and to provide additional constraints, more isospin-related observables will have to be put forward, with the aim of arriving at a more authentic final form of the density-dependent symmetry energy. Besides the sensitive observables being studied up to now by several theoretical groups in this field (Please see the review article [5]

BackgroundThe prevalence of drug-resistant tuberculosis (DR-TB) has brought severe challenges to the prevention and control of tuberculosis. Studies have explored the status of antituberculosis drug (ATD) resistance in different regions of China. However, few studies have focused on DR-TB in Sichuan to date. Due to the large population in Sichuan, detailed investigations of the DR-TB burden in Sichuan are needed. The objective of this study was to investigate the drug resistance characteristics of TB isolates from tuberculosis patients with and without HIV (TB-HIV patients and TBw/oHIV patients) in Chengdu, Sichuan, China.MethodsIsolates from respiratory samples of TBw/oHIV patients and TB-HIV patients hospitalized between January 2014 and December 2017 were collected. Nontuberculosis mycobacteria (NTM) were excluded. Drug sensitivity testing (DST) was performed according to the dilution method in microplates with 4 first-line ATDs and 8 second-line ATDs. TB strains were separated according to patient treatment history, patient age, calendar year and GeneXpert MTB/RIF (GeneXpert) assay results for further analysis.ResultsFor the 7470 patients recruited, the multidrug-resistant tuberculosis (MDR-TB) rate was 2.1-fold (14.6% vs. 6.8%) higher than the national baseline level. The repeatedly admitted patients were more likely to have a resistance profile than the first-time-admitted cases in both the TB-only group (P<0.05) and the TB-HIV corresponding group (P<0.05). Among the 7273 TBw/oHIV cases and 197 TB-HIV cases, the positivity rates of acid-fast bacilli (AFB) in the TB-HIV group were significantly lower than those in the TBw/oHIV group (P<0.05). The repeatedly admitted TB-HIV patients had lower resistance rates to INH than the repeatedly admitted TBw/oHIV patients (24.4% vs. 41.5%, P<0.05). The Rifampicin-resistant TB strains in the TBw/oHIV group were more likely to be resistant to INH in the repeatedly admitted group than those in the first-time admitted patients (P<0.05). The proportions of XDR (3.6% vs. 1.3%, P<0.05) and XDR-TB/MDR-TB (7.3% vs. 2.2%, P<0.05) in all TB-HIV patients were significantly higher than those in all TBw/oHIV patients. The ratio of XDR-TB was significantly higher in the TB-HIV group than in the TBw/oHIV group (30.4% vs. 9.0%, P<0.05) and the all TB group (9.0% vs. 10.1%, P<0.05). Regarding age, the <25-year-old TB-HIV patients (9.1% vs. 0.7%, P<0.05) and 25~44-year-old TB-HIV patients (5.2% vs. 2.4%, P<0.05) were more likely to have a higher XDR proportion than their TBw/oHIV counterparts. The ATD-resistance profile in terms of different years from high to low was 2014>2015>2016≈2017 for TBw/oHIV patients. The same trend was also observed for TB-HIV patients: 2014>2015>2016≈2017. The GeneXpert TB-positive rate in the TBw/oHIV group was higher than that in the TB-HIV group [81%(639/792) vs. 65% (13/20), P<0.05]. In TBw/oHIV cases, the agreement was 92.3% and the Kappa value was 0.75. In TB-HIV cases, the agreement was 85.0% and the Kappa value was 0.32.ConclusionIn Sichuan, ATD resista...

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Agropyron cristatum (L.) Gaertn. (2n = 4x = 28; genomes PPPP) is one of the wild species closely related to cultivated wheat (Triticum aestivum L.), which possesses a number of superior agronomic traits and thus represents a valuable resource for wheat improvement. Development of wheat–A. cristatum addition lines is usually considered to be the first step in transferring desirable alien genes into common wheat from A. cristatum. In this study, we report a novel wheat–A. cristatum 2P disomic addition line II‐9‐3, which contained 42 wheat chromosomes and a pair of A. cristatum chromosomes as revealed by genomic in situ hybridization. The homoeologous relationship between A. cristatum and wheat chromosomes was determined using specific‐locus amplified fragment sequencing markers specific to the A. cristatum 2P chromosome. Moreover, II‐9‐3 displayed high resistance to powdery mildew at both seedling and adult stages. Genetic analysis was conducted using an F2 population made by crossing II‐9‐3 with the susceptible cultivar Fukuhokomugi (Fukuho), and the results indicated that powdery mildew resistance was attributable to A. cristatum 2P chromosome in II‐9‐3. Besides, the resistance spectrum of II‐9‐3 was quite broad, as it was found resistant to all the 17 Bgt isolates prevalent in northern China. Taken together, this study will provide applicable methods for both genetically characterizing wheat addition lines with alien chromosomes and also novel germplasm potentially valuable in wheat resistance breeding.